Optimization of a liquid chromatography-tandem mass spectrometry method for the quantification of traces of taxanes in a Corylus avellana cell suspension medium
Since the recent discovery of taxol and other taxanes in Corylus avellana, this plant species has attracted interest as a potential new source of these compounds. However, its low taxane content in comparison with Taxus spp. has restricted research to analytical identification or global quantitation. A feasible and sensitive method based on liquid chromatography-tandem mass spectrometry using a triple quadrupole analyzer was developed for the analysis of taxol and four other taxanes in a Corylus avellana cell suspension medium. Taxanes were extracted from the cell culture medium with dichloromethane and analyzed using electrospray ionization and quantified by multiple-reaction monitoring mode. Methanol and matrix-matching calibration curves using docetaxel as the internal standard were analyzed. Linearity was confirmed over the whole calibration range (0.3–2.1 μg mL−1). The inter- and intra-day precision of taxanes ranged from 80% to 120% and the recovery rates were higher than 80%. Limits of detection were between 0.24–38 ng mL−1 and the limits of quantification were between 0.8–125 ng mL−1. The low detection and quantitation values obtained allowed us to detect small quantities of the released taxanes (120 ng mL−1 of B, 151 ng mL−1 of CF and 105 ng mL−1 of T), which correspond to about 0.5 ng mL−1 of each taxane, in the 20 mL Corylus avellana cell suspension culture medium extracted, even at the beginning of the culture. These results were confirmed by high resolution mass spectrometry.